[PATCH] New fstest to check rename POSIX conformance

[Andre Marques]

Sorry for the delay.

I'm almost ready to send the patch with the test, but there are some 
questions.

On 02/10/14 08:14, Sebastian Huber wrote:
> Hello Andre,
>
> thanks for the test case.
>
> On 2014-02-08 13:26, Andre Marques wrote:
>> Hi,
>>
>> As discussed in [1], I created a new fstest to check the rename()
>> implementation against the POSIX specification [2].
>>
>> What the attached patch does not test:
>>
>> - Testing the existance of a link visible to other processes during 
>> the rename
>> process (ensuring that there is always a reference to the file). Not 
>> sure about
>> the best way to test this.
>
> The file system instance is locked during the rename operation, so 
> other threads cannot interfere here.
>

Should I test the lock then?

> What happens if you rename a file with an open file descriptor should 
> be tested.

That is already covered on the test.

>
>>
>> - Testing that after all processes close their references to a file 
>> after it
>> was removed by rename() the file contents are removed (or marked as 
>> free space,
>> I guess). I only found platform dependent ways of dealing with disk 
>> block's.
>
> Maybe you can use the statvfs() function for this.

The statvfs() function gives "not implemented" on the IMFS filesystem, 
so I changed the used filesystem to MOUNTED RFS.

>
>>
>> - Testing errno values in error situations. There is already a fstest 
>> named
>> fserror which purpose seems to be checking errno values for a bunch of
>> functions (rename included, but with some errno values missing). Not 
>> sure if I
>> should put them in this test or add to fserror.
>
> I would move all rename related tests to this new test program.

About the errno value testing, I'm currently missing EIO, ENOSPC, EROFS 
and EXDEV.

EROFS and EXDEV require mounting a second filesystem. How can I do this 
in RTEMS? Can it be done at runtime? I've been looking at the fileio 
sample, which uses the fsmount() function, but I need a disk to mount 
with it.

For ENOSPC I'm thinking in mounting a small disk and testing that way, 
but for EIO I don't know how to simulate a physical error. How can I 
generate an I/O error?

>
>>
>>
>> This test uses the MOUNTED IMFS filesystem, for no particular reason, 
>> so if
>> that's an issue please let me know.
>>
>> [1] - 
>> http://www.rtems.org/pipermail/rtems-users/2014-January/012378.html
>>
>> [2] - 
>> http://pubs.opengroup.org/onlinepubs/9699919799/functions/rename.html
>>
>> --André Marques
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